In woodworking, a power sander is often used to smooth or alter the shape of a piece of wood. When sanding contours, e.g., on the edge of the wood, a drum sander is typically placed on a portion of the wood with a small surface area and manipulated with a single handle to pass back and forth over the wood to smooth and shape the surface of the contour. Unfortunately, conventional drum sanders prove to be very unstable when used in this manner and can damage a piece of wood if not controlled properly.
One power sander is described in U.S. Pat. No. 3,656,920 that issued to Hosea W. Helms on Apr. 18, 1972 (the "Helms patent"). The Helms patent describes a power sanding device for sanding irregular surfaces with an abrasive cylinder mounted on a drive shaft. The power sanding device includes a radial handle rotatably mounted on one end of the drive shaft and a flexible shaft, disposed at an opposite end of the drive shaft, that is capable of transmitting torque through an angle to the drive shaft. The flexible shaft is connectable to a portable power drill to rotate the abrasive cylinder. This allows a user to keep the common axes of the knuckles of each hand generally perpendicular to the axis of the abrasive cylinder. However, the Helms patent describes a sanding device with a limited range of capabilities.
Pneumatic drum sanders are described in Catalog No. PS-8 from Ekstrom, Carlson & Co., Small Tools Division of Rockford, Ill. These sanders include an air-inflated drum with a ball bearing handle. A detachable air tool or a power drill powers the sander. When the air tool is used, an air inlet port is coupled to a source of compressed air. Unfortunately, these drum sanders also have a limited range of capabilities and are typically used in combination with other equipment.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a versatile, power sander with increased stability when sanding contours.